Preheat oven to 350°F and line hazelnuts on a baking sheet.
Bake hazelnuts in oven for 12-15 minutes on the middle rack until the smell of toasted hazelnuts is prevalent and they've started to turn slightly golden brown.
Remove from oven and let cool completely, about 10 minutes (in the fridge) up to one hour (on the counter).
Using a double boiler pan (a glass bowl on top of a saucepan filled with boiling water), melt semi-sweet chocolate chips until melted. When melted, remove from heat and let cool for about 10 minutes.
In a Vitamix blender (or food processor but blender delivered best results) add nuts in and turn to medium-high speed. Grind until nuts become crumbled like sand and may stick together to form a paste.
Add oil, sugar, cocoa powder, vanilla, and salt and continue processing until a thick, well-mixed paste occurs.
Add the melted chocolate to the blender and let blend together until a perfectly smooth paste is create.
Scrape your homemade chocolate hazelnut spread into a Le Parfait Jars and use as desired. Will last up to 2 weeks on the counter or up to 2 months in the fridge.